Nanoparticles of co complexes of zero-valent metals that can be  used as hydrosilylation and dehydrogenative silylation catalysts

ABSTRACT

Nanoparticles that can be used as hydrosilylation and dehydrogenative silylation catalysts. The nanoparticles have at least one transition metal with an oxidation state of 0, chosen from the metals of columns 8, 9 and 10 of the periodic table, and at least one carbonyl ligand, preferably a silicide.

FIELD OF THE INVENTION

The invention relates to nanoparticles that can be used as catalysts, inparticular as hydrosilylation and dehydrogenative silylation catalysts.More specifically, the present invention relates to nanoparticlescomprising at least one transition metal with an oxidation state of 0,chosen from the metals of columns 8, 9 and 10 of the periodic table, andat least one carbonyl ligand.

TECHNOLOGICAL BACKGROUND

During a hydrosilylation reaction (also called polyaddition), a compoundcomprising at least one unsaturation reacts with a compound comprisingat least one hydrogenosilyl function, i.e. a hydrogen atom bonded to asilicon atom. This reaction can for example be described in the case ofan unsaturation of the alkene type by:

or in the case of an unsaturation of the alkyne type by:

During a dehydrogenative silylation reaction, the reaction can bedescribed by:

The hydrosilylation of unsaturated compounds is carried out bycatalysis. Typically, the suitable catalyst for this reaction is aplatinum catalyst. Currently, most industrial hydrosilylation reactionsare catalysed by the Karstedt platinum complex, having the generalformula Pt₂(divinyltetramethyldisiloxane)₃ (or in shortened formPt₂(DVTMS)₃):

However, this type of catalyst is relatively unstable and changes overthe course of the reaction by forming colloidal species of Pt(0), ofwhich the size is not controlled, which leads to a coloration of thereaction medium and of the oil obtained ranging from yellow to black.

In this context, it would therefore be interesting to access effectivealternative catalysts, of which the preparation, implementation andactivity can be reproduced, for hydrosilylation or dehydrogenativesilylation reactions.

One of the objectives of the present invention is therefore to propose acatalyst, adapted in particular for the catalysis of hydrosilylation anddehydrogenative silylation reactions, that is effective.

Another objective of the invention is to provide a method ofhydrosilylation implementing a catalyst that is effective.

BRIEF DESCRIPTION OF THE INVENTION

These objectives are achieved thanks to the implementation ofnanoparticles comprising at least one transition metal with an oxidationstate of 0, chosen from the metals of columns 8, 9 and 10 of theperiodic table, and at least one carbonyl ligand, as a hydrosilylationor dehydrogenative silylation catalyst.

Thus, the present invention has for object nanoparticles comprising:

-   -   at least one transition metal with an oxidation state of 0,        chosen from the metals of columns 8, 9 and 10 of the periodic        table, and    -   at least one carbonyl ligand.

The invention also has for object a colloidal suspension comprisingnanoparticles.

The invention also has for object a catalyst comprising nanoparticles ora colloidal suspension comprising nanoparticles.

The invention also has for object a method for preparing nanoparticlesand/or a colloidal suspension comprising nanoparticles.

The invention also has for object a method of hydrosilylation catalysedby nanoparticles or a colloidal suspension comprising nanoparticles.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A shows a HAADF STEM photo of the colloidal solution comprisingiron nanoparticles according to example 1. FIG. 1B shows a histogram ofthe diameter of the iron nanoparticles according to example 1.

FIG. 2 shows the infrared spectrum of the iron nanoparticles accordingto example 1 and of the iron precursor used.

FIG. 3 shows the ¹³C-NMR spectrum of the iron nanoparticles according toexample 1 and of the iron precursor used.

FIG. 4 shows the ¹H-NMR spectrum of the iron nanoparticles according toexample 1 and of the n-octylsilane.

FIG. 5A shows a HAADF STEM photo of the colloidal solution comprisingcobalt nanoparticles according to example 2. FIG. 5B shows a histogramof the diameter of the cobalt nanoparticles according to example 2according to their diameter.

FIG. 6 shows the infrared spectrum of the cobalt nanoparticles accordingto example 2 and of the cobalt precursor used.

FIG. 7 shows the ¹³C-NMR spectrum of the cobalt nanoparticles accordingto example 2 and of the cobalt precursor used.

FIG. 8 shows the ¹H-NMR spectrum of the cobalt nanoparticles accordingto example 2 and of the n-octylsilane.

FIG. 9 shows the Mossbauer spectrum of the iron nanoparticles accordingto example 1.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

“Silane” means in the present invention the chemical compoundscomprising a silicon atom bonded to four hydrogen atoms or to organicsubstituents. “Polysilane” means in the present invention the chemicalcompounds having at least one unit ≡Si—Si≡.

“Hydrogenosilane” means in the present invention the chemical compoundsbelonging to the group of silanes, comprising therefore at least onesilicon atom, and comprising at least one hydrogen atom bonded to thesilicon atom.

“Organopolysiloxane” means in the present invention the chemicalcompounds having at least one unit ≡Si—O—Si≡.

“Alkyl” means a hydrocarbon chain, linear or branched, comprising from 1to 40 carbon atoms, preferably from 1 to 20 carbon atoms, morepreferably from 1 to 10 carbon atoms. An alkyl group can be chosen fromthe group consisting of methyl, ethyl, isopropyl, n-propyl, tert-butyl,isobutyl, n-butyl, n-pentyl, isoamyl and 1,1-dimethylpropyl.

“Cycloalkyl” means according to the invention a monocyclic or polycyclicsaturated hydrocarbon group, preferably monocyclic or bicyclic,containing from 3 to 20 carbon atoms, preferably from 5 to 8 carbonatoms. When the cycloalkyl group is polycyclic, the multiple cycliccores can be attached to one another by a covalent bond and/or by aspiro atom and/or be condensed to one another. A cycloalkyl group can bechosen from the group consisting of cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantane andnorborane.

“Aryl” means according to the invention an aromatic hydrocarbon groupcontaining from 5 to 18 carbon atoms, monocyclic or polycyclic. An arylgroup can be chosen from the group consisting of phenyl, naphthyl,anthracenyl and phenanthryl.

“Halogen atom” means according to the invention an atom chosen from thegroup consisting of fluorine, chlorine, bromine and iodine.

“Heteroaryl” means according to the invention an aryl group wherein atleast one carbon atom has been substituted with a heteroatom chosen fromO, N, S and P. A heteroaryl group can be chosen from the groupconsisting of pyranyl, furanyl, pyridinyl, pyrimidinyl, pyrrolyl,pyrazolyl, imidazolyl, isothiazolyl, isoxazolyl and indolyl.

“Heterocycloalkyl” means according to the invention a cycloalkyl groupwherein at least one carbon atom has been substituted with a heteroatomchosen from O, N, S and P. Preferably the heterocycloalkyl comprisesfrom 5 to 10 members. A heterocycloalkyl group can in particular be themonocyclic oxiranyl group or the bicyclic epoxycyclohexyl group.

“Alkoxy” means according to the invention an alkyl group such as definedhereinabove bonded to an oxygen atom. An alkoxy group can be chosen fromthe group consisting of methoxy, ethoxy, propoxy and butoxy.

“Aryloxy” means according to the invention an aryl group such as definedhereinabove bonded to an oxygen atom. An aryloxy group can be forexample the phenoxy group.

“Cycloalkoxy” means according to the invention a cycloalkyl group suchas defined hereinabove bonded to an oxygen atom.

“Alkylsilyl” means according to the invention an alkyl group such asdefined hereinabove bonded to a silicon atom.

“Alkoxysilyl” means according to the invention an alkoxy group such asdefined hereinabove bonded to a silicon atom.

Nanoparticies

The present invention has for object nanoparticles comprising:

-   -   at least one transition metal with an oxidation state of 0,        chosen from the metals of columns 8, 9 and 10 of the periodic        table, and    -   at least one carbonyl ligand.

In the present invention, the metals of columns 8, 9 and 10 of theperiodic table are preferably iron (Fe), ruthenium (Ru), osmium (Os),cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd) andplatinum (Pt). Preferably, the nanoparticles include at least one metalchosen from the group consisting of Fe, Ru, Os, Co, Rh, Ir, Ni, Pd andPt, and more preferably in the group consisting of Fe, Co and Ni, or inthe group consisting of Fe and Co.

The nanoparticles can also include several metals chosen from the metalsof columns 8, 9 and 10 of the periodic table. The nanoparticles can, forexample, include 2 or 3 metals.

It is thus possible to have bimetallic or trimetallic nanoparticles,such as nanoparticles comprising the metals Fe and Co, or the metals Feand Ni, or the metals Co and Ni, or nanoparticles comprising the metalsFe, Co and Ni. The metal or metals contained in the nanoparticles arewith an oxidation state of 0.

The nanoparticles also comprise at least one carbonyl ligand (CO). Thiscarbonyl ligand is coordinated with at least one metal atom of columns8, 9 or 10 of the periodic table. This ligand can be coordinated at thesurface of the nanoparticles. The presence of the carbonyl ligand can bedetermined by infrared spectroscopy (IR), or by ¹³C-NMR.

Advantageously, the nanoparticles also comprise at least one silicide.In the present invention, “silicide” means the chemical compoundscomprising a silicon atom bonded to at least one metal atom chosen fromthe metals of columns 8, 9 and 10 of the periodic table. Preferably, thesilicide also comprises at least one Si—C bond. The silicide can bechosen from compounds having formula (I):

Y_(p)Z⁴ _(q)SiH_(r)   (I)

wherein:

-   -   the symbol(s) Y, identical or different, represent a metal        chosen from the metals of columns 8, 9 and 10 of the periodic        table, preferably a metal chosen from Fe, Co and Ni, and more        preferably Fe and Co;    -   the symbol(s) Z⁴, identical or different, represent a monovalent        hydrocarbon group having from 1 to 18 carbon atoms inclusive        optionally substituted with heteroatoms or with radicals        comprising heteroatoms, and preferably chosen from the group        consisting of alkyl groups having from 1 to 18 carbon atoms        inclusive and aryl groups having from 6 to 12 carbon atoms, and        more preferably chosen from the group consisting of alkyl groups        having 4 to 12 carbon atoms inclusive;    -   p=1, 2 or 3;    -   q=1, 2 or 3, preferably q=1;    -   r=0, 1 or 2;    -   p+q+r=4.        The symbol(s) Z⁴, identical or different, can represent a linear        alkyl group having 4 to 12 carbon atoms inclusive. Among the        linear alkyl groups having 4 to 12 carbon atoms inclusive,        mention can be made of n-butyl, n-pentyl, n-hexyl, n-heptyl,        n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl. According to an        embodiment, q=1 and the symbol V represents an n-octyl group.

The size of the nanoparticles can be variable. Preferably, thenanoparticles have an average diameter less than or equal to 50 nm, orless than or equal to 10 nm. More preferably, the nanoparticles have anaverage diameter less than or equal to 10 nm, or less than or equal to 5nm, or less than or equal to 3 nm. The average diameter can be comprisedbetween 0.5 and 10 nm, or between 0.5 and 5 nm, or between 0.75 and 3nm. The average diameter of the nanoparticles can, for example, bedetermined by transmission electron microscopy.

According to an embodiment, the nanoparticles have an average diameterless than or equal to 10 nm, and comprise:

-   -   at least one metal chosen from the metals of columns 8, 9 and 10        of the periodic table;    -   at least one carbonyl ligand, and    -   at least one silicide.

According to an embodiment, the nanoparticles have an average diameterless than or equal to 5 nm, and comprise:

-   -   at least one metal chosen from Fe, Co and Ni;    -   at least one carbonyl ligand, and    -   at least one silicide chosen from compounds having formula (I):

Y_(p)Z⁴ _(q)SiH_(r)   (I)

wherein:

-   -   the symbol(s) Y, identical or different, represent a metal        chosen from the metals of columns 8, 9 and 10 of the periodic        table, preferably a metal chosen from Fe, Co and Ni;    -   the symbol(s) Z⁴, identical or different, represent a monovalent        hydrocarbon group having from 1 to 18 carbon atoms inclusive        optionally substituted with heteroatoms or with radicals        comprising heteroatoms, and preferably chosen from the group        consisting of alkyl groups having from 1 to 18 carbon atoms        inclusive and aryl groups having from 6 to 12 carbon atoms, and        more preferably chosen from the group consisting of alkyl groups        having 4 to 12 carbon atoms inclusive;    -   p=1, 2 or 3;    -   q=1, 2 or 3, preferably q=1;    -   r=0, 1 or 2;    -   p+q+r=4.

Advantageously, the nanoparticles are not paramagnetic.

According to an embodiment, the nanoparticles have an average diameterless than or equal to 50 rim, and comprise:

-   -   at least one metal chosen from the metals of columns 8, 9 and 10        of the periodic table;    -   at least one carbonyl ligand, and    -   at least one silicide, preferably silicide chosen from compounds        having formula (I):

Y_(p)Z⁴ _(q)SiH_(r)   (I)

wherein:

-   -   the symbol(s) Y, identical or different, represent a metal        chosen from the metals of columns 8, 9 and 10 of the periodic        table, preferably a metal chosen from Fe, Co and Ni;    -   the symbol(s) Z⁴, identical or different, represent a monovalent        hydrocarbon group having from 1 to 18 carbon atoms inclusive        optionally substituted with heteroatoms or with radicals        comprising heteroatoms, and preferably chosen from the group        consisting of alkyl groups having from 1 to 18 carbon atoms        inclusive and aryl groups having from 6 to 12 carbon atoms, and        more preferably chosen from the group consisting of alkyl groups        having 4 to 12 carbon atoms inclusive;    -   p=1, 2 or 3;    -   q=1, 2 or 3, preferably q=1;    -   r=0, 1 or 2;    -   p+q+r=4.

The invention also has for object a colloidal suspension comprisingnanoparticles such as described hereinabove. The nanoparticles can be insuspension in an organic solvent, preferably an aprotic solvent. Thesolvent can be chosen from the group consisting of:

-   -   aromatics, preferably toluene,    -   alkanes, preferably pentane,    -   ethers, preferably THF,    -   and mixtures thereof.

The nanoparticles can also be in suspension in a silicone oil,preferably a silicone oil that has a dynamic viscosity less than orequal to 100,000 mPa.s at 25° C.

The nanoparticles can be placed in suspension in a silicone oil in thefollowing manner:

-   -   adding of a silicone oil in a colloidal suspension comprising        nanoparticles and an organic solvent, and    -   evaporation of the organic solvent.

This colloidal suspension can have a concentration in starting metalcomprised between 1 and 100 μmol/mL, preferably between 10 and 50μmol/mL.

The invention also has for object a catalyst comprising nanoparticles oftransition metals with an oxidation state of 0 such as describedhereinabove or a colloidal suspension such as described hereinabove.This catalyst can be a hydrosilylation and/or dehydrogenative silylationcatalyst. This catalyst can also be an alkene isomerisation catalyst.

The invention also has for object the use of nanoparticles of transitionmetals with an oxidation state of 0 such as described hereinabove or acolloidal suspension such as described hereinabove as a catalyst,preferably as a hydrosilylation and/or dehydrogenative silylation and/oralkene isomerisation catalyst.

Method for Preparing Nanoparticles

The invention also has for object a method for preparing nanoparticlesor a colloidal suspension comprising nanoparticles. This methodcomprises a step of mixing at least one metal complex, chosen from thetransition metal carbonyls of columns 8, 9 and 10 of the periodic table,with at least one silane in a solvent, under inert atmosphere and/orunder hydrogen.

The silane will react with the metal complex to form a silicide. Themetal complex is chosen from the transition metal carbonyls of columns8, 9 and 10 of the periodic table, it is therefore a complex of atransition metal chosen from the metals of columns 8, 9 and 10 of theperiodic table comprising at least one carbonyl ligand. Preferably, itis an iron, cobalt or nickel carbonyl, among which mention can be madeof: Fe₃(CO)₁₂, Fe₂(CO)₉, Fe(CO)₅, Co₂(CO)₈, Co₄(CO)₁₂ and Ni(CO)₄.Advantageously, the metal complex is chosen from the iron or cobaltcarbonyls.

It is also possible to use several different metal complexes, forexample if it is desired to synthesise bimetallic or trimetallicnanoparticles.

Advantageously, the silane comprises at least one Si—C bond and at leastone Si—H bond. This is preferably a silane having formula (II):

V⁴ _(q)SiH_((4−q))   (II)

wherein Z⁴ and q have the same meaning as hereinabove.

The quantity of silane used in the method is at least 0.01 molarequivalents with respect to the metal comprised in the metal compleximplemented. This quantity can be comprised between 0.01 and 5 molarequivalents with respect to the metal comprised in the metal compleximplemented. Preferably, this quantity is comprised between 0.01 and 1,and more preferably, between 0.05 and 0.5 molar equivalents with respectto the metal comprised in the metal complex implemented. The quantity ofsilane can have an influence on the size of the nanoparticles.Advantageously, to prepare nanoparticles having an average diameter lessthan or equal to 50 nm, or a colloidal suspension comprising suchnanoparticles, the quantity of silane is comprised between 0.01 and 1molar equivalent in relation to the metal comprised in the metalcomplex, preferably between 0.05 and 0.5 molar equivalents.

The solvent is an organic solvent, preferably an aprotic solvent. Thesolvent can be chosen from the group consisting of:

-   -   aromatics, preferably toluene,    -   alkanes, preferably pentane,    -   ethers, preferably THF,    -   and mixtures thereof.

The method for preparing nanoparticles is carried out under an inertatmosphere and/or under hydrogen. “Inert atmosphere” means anon-reactive gas in the reaction conditions. Among the non-reactivegases, mention can be made of dinitrogen and the noble gases (helium,argon, krypton and xenon). According to an embodiment of the method, themethod is carried out under dinitrogen or under argon.

According to an embodiment of the method, the mixing step is carried outat a temperature less than 140° C., preferably comprised between 10 and135° C., between 10 and 120° C., or between 10 and 90° C. According toan embodiment of the method for preparing nanoparticles, the mixing stepis carried out at room temperature.

According to an embodiment of the method for preparing nanoparticles,the mixing step is carried out under a hydrogen pressure comprisedbetween 1 and 10 bars, preferably, between 1 and 5 bars.

According to an embodiment of the method for preparing nanoparticles,the step of mixing lasts at least 30 minutes, preferably between 1 and25 hours. According to an embodiment of the method, the step of mixinglasts at least 15 hours, preferably, between 15 and 25 hours.

The invention also has for object nanoparticles and/or a colloidalsuspension comprising nanoparticles able to be obtained by the methoddescribed hereinabove.

Method of Hydrosilylation

The present invention also has for object a method for preparinghydrosilylation and/or dehydrogenative silylation products by reaction

-   -   between an unsaturated compound A, and    -   a compound B comprising at least one hydrogenosilyl function,    -   said method being characterised by the fact that it is catalysed        by nanoparticles and/or a colloidal suspension comprising        nanoparticles such as described hereinabove.

The unsaturated compound A according to the invention is a compoundcomprising at least one unsaturation that is not part of an aromaticcycle. Compound A comprises in particular at least one alkene functionand/or an alkyne function. Any compound that comprises at least onealkene function and/or an alkyne function can be used in the methodaccording to the invention, in that it does not contain any reactivechemical function that can hinder, even prevent the hydrosilylationreaction.

According to an embodiment, compound A comprises one or more alkenefunctions and from 2 to 40 carbon atoms. It can further comprise 1 to 20heteroatoms chosen from N, P, O, S, F, Cl, Br and I. When compound Acomprises several alkene functions, the latter can be conjugated or not.

According to another embodiment, compound A comprises one or more alkynefunctions and from 2 to 40 carbon atoms. It can further comprise 1 to 20heteroatoms chosen from N, P, O, S, F, Cl, Br and I. When compound Acomprises several alkyne functions, the latter can be conjugated or not.

Compound A can be chosen from compounds having formula (III) or (IV):

wherein:

-   -   R¹, R², R³ and R⁴ represent, independently of one another,        -   a hydrogen atom;        -   a halogen atom chosen from fluorine, chlorine, bromine and            iodine;        -   an alkyl group;        -   a cycloalkyl group;        -   an aryl group;        -   a heteroaryl group;        -   a heterocycloalkyl group;        -   an alkoxy group;        -   an aryloxy group;        -   a cycloalkoxy group;        -   an alkylsilyl group;        -   an alkoxysilyl group;        -   a carboxylic acid group;        -   an alkylic esters group;        -   a urea group;        -   an amide group;        -   a sulfonamide group;        -   an imide group;        -   a cyano group;        -   an aldehyde group;        -   an alcohol group;        -   a thiol group;        -   an amine group;        -   an imine group;        -   a sulphide group;        -   a sulphoxide group;        -   a sulfone group;        -   an azide group;        -   an allyl phosphonate group; or        -   an allyl phosphate group;    -   these groups are able themselves to be substituted on their        alkyl and/or cycloalkyl and/or aryl portion(s) with:        -   one or more C1 to C8 alkyl groups, optionally halogenated;        -   one or more C1 to C8 alkoxy groups, optionally halogenated;        -   one or more aryl groups, optionally halogenated;        -   one or more halogen atoms;        -   one or more carboxylic acid groups;        -   one or more ester groups;        -   one or more ether groups;        -   one or more urea groups;        -   one or more amide groups;        -   one or more sulfonamide groups;        -   one or more imide groups;        -   one or more cyano groups;        -   one or more aldehyde groups;        -   one or more ketone function groups;        -   one or more alcohol groups;        -   one or more thiol groups;        -   one or more amine groups;        -   one or more imine groups;        -   one or more sulphide groups;        -   one or more sulphoxide groups;        -   one or more sulfone groups;        -   one or more azide groups;        -   one or more phosphate groups; and/or        -   one or more phosphonate groups;    -   or    -   at least two groups chosen from R¹, R², R³ and R⁴ form together        with the carbon atoms to which they are bonded one or more        cycloalkyl, heterocycloalkyl, aryl or heteroaryl groups, these        groups, cycloalkyl, heterocycloalkyl, aryl and heteroaryl able        to be substituted with one or more C1 to C8 alkyl groups,        optionally halogenated; with one or more C1 to C8 alkoxy groups,        optionally halogenated; with one or more aryl groups, optionally        halogenated; with one or more halogen atoms; with one or more        carboxylic acid groups; with one or more ester groups; with one        or more ether groups, with one or more urea groups; with one or        more amide groups; with one or more sulfonamide groups; with one        or more imide groups; with one or more cyano groups; with one or        more aldehyde groups; with one or more ketone functions; with        one or more alcohol groups; with one or more thiol groups; with        one or more amine groups; with one or more imine groups; with        one or more sulphide groups; with one or more sulphoxide groups;        with one or more sulfone groups; with one or more azide groups;        with one or more phosphate groups; and/or with one or more        phosphonate groups;    -   the remaining groups among R¹, R², R³ and R⁴ being such as        defined hereinabove,    -   and mixtures thereof.

Preferably, R¹, R², R³ and R⁴ represent, independently of one another:

-   -   a hydrogen atom;    -   a C1 to C16 alkyl group, optionally substituted with a hydroxy        group or a halogen atom;    -   a phenyl, optionally substituted with a C1 to C4 alkyl group,        with a halogen, with a C1 to C4 alkyl group itself substituted        with one or more halogens, with a C1 to C4 alkoxy group or with        an amine function optionally substituted one or two times with a        C1 to C4 alkyl group;    -   a pyridine;    -   a C1 to C8 alkylic ester;    -   a cyano function;    -   a carboxylic acid function;    -   a C1 to C4 acyloxy group, in particular acetyloxy;    -   a primary amide group, in particular unsubstituted on the        nitrogen or substituted one or two times with a C1 to C4 alkyl        group; or    -   a polyethoxyl alkyl group, optionally substituted with a hydroxy        or a ketone.

Advantageously, R¹ can be a hydrogen atom, and R³ can represent asubstituent different from a hydrogen atom. In the case of a compoundhaving formula (I), R² and R⁴ can furthermore be hydrogen atoms.

Preferably, compound (A) can also be chosen from the group consistingof:

-   -   C1 to C4 alkyl acrylates and methacrylates;    -   acrylic acid or methacrylic acid;    -   acetylene;    -   alkenes, preferably octene and more preferably 1-octene;    -   non-conjugated dienes and preferably hexadiene or octadiene;    -   allylic alcohol;    -   allylamine;    -   ether glycidyl allyl;    -   allyl and piperidine ether and preferably allyl and piperidine        ether sterically hindered allyl and piperidine ether;    -   styrene and preferably alpha-methyl-styrene;    -   1,2-epoxy-4-vinylcyclohexane;    -   chlorinated alkenes and preferably allyl chloride;    -   fluorinated alkenes and preferably        4,4,5,5,6,6,7,7,7-nonafluoro-1-heptene, and mixtures thereof.

Compound (A) can also be chosen from the compounds comprising severalalkene functions, preferably two or three alkene functions, andparticularly preferably chosen from the following compounds:

with p equalling 1 or 2,

and mixtures thereof.

It is also possible in the framework of the invention to have a mixtureof aforementioned compounds (A) comprising an alkene function and ofaforementioned compounds (A) comprising several alkene functions.

Compound (A) can therefore also comprise chemical functions that make itpossible to chemically modify the compound obtained following thehydrosilylation reaction.

The hydrosilylation of compounds that comprise both one or more doubleethylenic bonds and one or more triple acetylenic bonds is alsoconsidered in the framework of the invention.

According to a preferred embodiment, the unsaturated compound A ischosen from the organopolysiloxane compounds including units havingformula (V):

Z_(g)U_(h)SiO_((4−(g+h))/2)   (V)

wherein:

-   -   the Z radicals, identical or different, represent an alkenyl or        alkynyl radical, linear or branched, having from 2 to 6 carbon        atoms;    -   the U radicals, identical or different, represent a hydrocarbon        radical having from 1 to 12 carbon atoms,    -   g=1 or 2, h=0, 1 or 2 and g+h=1, 2 or 3;    -   and including optionally other units having formula (VI):

U_(i)SiO_((4−i)/2)   (VI)

wherein U has the same meaning as hereinabove, and i=0, 1, 2, or 3.

It is understood in the formula (V) and in the formula (VI) hereinabovethat, if several U groups are present, they can be identical ordifferent from one another. In the formula (V), the symbol g canpreferably be equal to 1.

In the formula (V) and in the formula (VI), U can represent a monovalentradical chosen from the group consisting of alkyl groups having 1 to 8carbon atoms, optionally substituted with at least one halogen atom suchas chlorine or fluorine, the cycloalkyl groups having from 3 to 8 carbonatoms and the aryl groups having from 6 to 12 carbon atoms. U canadvantageously be chosen from the group consisting of methyl, ethyl,propyl, 3,3,3-trifluoropropyl, xylyl, tolyl and phenyl.

Said organopolysiloxanes can be oils with a dynamic viscosity of aboutfrom 10 to 100,000 mPa.s at 25° C., generally of about from 10 to 70,000mPa.s at 25° C., or gums with a dynamic viscosity of about from1,000,000 mPa.s or more at 25° C.

All of the viscosities concerned in the present disclosure correspond toa magnitude of dynamic viscosity at 25° C. referred to as “Newtonian”,i.e. the dynamic viscosity which is measured, in a manner known per se,with a Brookfield viscosimeter with a shear velocity gradient that islow enough for the viscosity measured to be independent of the velocitygradient.

These organopolysiloxanes can have a linear, branched or cyclicstructure. Their degree of polymerisation is, preferably, comprisedbetween 2 and 5000.

When this entails linear polymers, the latter are substantiallyconsisted of “D” siloxyl units chosen from the group consisting of thesiloxyl units Z₂SiO_(2/2), ZUSiO_(2/2) and U₂SiO_(2/2), and of “M”siloxyl units chosen from the group consisting of the siloxyl unitsZU₂SiO_(1/2), Z₂USiO_(1/2) and Z₃SiO_(1/2). The symbols Z and U are suchas described hereinabove.

As examples of “M” terminal units, mention can be made of thetrimethylsiloxy, dimethylphenylsiloxy, dimethylvinylsiloxy ordimethylhexenylsiloxy groups.

With regards to examples of “D” units, mention can be made of thedimethylsiloxy, methyiphenylsiloxy, methylvinylsiloxy,methylbutenylsiloxy, methylhexenylsiloxy, methyldecenylsiloxy ormethyldecadienylsiloxy groups.

Examples of linear organopolysiloxanes that can be unsaturated compoundsA according to the invention are:

-   -   a poly(dimethylsiloxane) with dimethylvinylsilyl ends;    -   a poly(dimethylsiloxane-co-methylphenylsiloxane) with        dimethyl-vinylsilyl ends;    -   a poly(dimethylsiloxane-co-methylvinylsiloxane) with        dimethyl-vinylsilyl ends; and    -   a poly(dimethylsiloxane-co-methylvinylsiloxane) with        trimethyl-silyl ends; and    -   a cyclic poly(methylvinylsiloxane).

The cyclic organopolysiloxanes that can also be unsaturated compounds Aaccording to the invention are for example, those consisted of “D”siloxyl units having the following formulas: Z₂SiO_(2/2), U₂SiO_(2/2) orZUSiO_(2/2), which can be of the dialkylsiloxy, alkylarylsiloxy,alkylvinylsiloxy, alkylsiloxy type. Said cyclic organopolysiloxanes havea viscosity of about from 10 to 5,000 mPa.s at 25° C.

According to another embodiment, it is possible to implement in themethod according to the invention a second organopolysiloxane compoundincluding, per molecule, at least two C₂-C₆ alkenyl radicals bonded tosilicon atoms, different from the organopolysiloxane compound A, saidsecond organopolysiloxane compound being preferablydivinyltetramethylsiloxane (DVTMS).

Preferably, the organopolysiloxane compound A has a mass content inSi-vinyl units comprised between 0.001 and 30%, preferably between 0.01and 10%.

As other examples of unsaturated compounds A mention can be made of thesilicone resins comprising at least one vinyl radical. For example theycan be chosen from the group consisting of the following siliconeresins:

-   -   MD^(Vi)Q where the vinyl groups are included in the units D,    -   MD^(Vi)TQ where the vinyl groups are included in the units D,    -   MM^(Vi)Q where the vinyl groups are included in a portion of the        units M,    -   MM^(Vi)TQ where the vinyl groups are included in a portion of        the units M,    -   MM^(Vi)DD^(Vi)Q where the vinyl groups are included in a portion        of the units M and D,    -   and mixtures thereof,    -   with:    -   M^(Vi)=sitoxyl unit having formula (R)₂(vinyl)SiO_(1/2)    -   D^(Vi)=siloxyl unit having formula (R)(vinyl)SiO_(2/2)    -   T=siloxyl unit having formula (R)SiO_(3/2)    -   Q=siloxyl unit having formula SiO_(4/2)    -   M=siloxyl unit having formula (R)₃SiO_(1/2)    -   D=siloxyl unit having formula (R)/SiO_(2/2)    -   and the R groups, identical or different, are monovalent        hydrocarbon groups chosen from the alkyl groups having from 1 to        8 carbon atoms inclusive such as the methyl, ethyl, propyl and        3,3,3-trilluoropropyl groups and the aryl groups such xylyl,        tolyl and phenyl. Preferably, the R groups are methyls.

The method according to the invention also implements a compound Bcomprising at least one hydrogenosilyl function, i.e. at least onehydrogen atom directly bonded to a silicon atom (or at least one Si—Hgroup).

Preferably, compound B comprising at least one hydrogenosilyl functionis chosen from the group consisting of:

-   -   a hydrogenosilane compound,    -   an organopolysiloxane compound comprising at least one hydrogen        atom bonded to a silicon atom, preferably an organopolysiloxane        compound comprising per molecule at least two hydrogenosilyl        functions, and    -   an organic polymer comprising hydrogenosilyl functions in        terminal positions.

Preferably, the silicon atoms of the compounds (B) are bonded to morethan one hydrogen atom.

Compound (B) can be a hydrogenosilane compound. Preferably, thehydrogenosilane compound according to the invention comprises less than5 silicon atoms.

Any hydrogenosilane compound can be used in the method according to theinvention, in that it does not contain any reactive chemical functionthat can hinder, even prevent the hydrosilylation reaction.

According to an embodiment of the present invention, the hydrogenosilanecompound can be chosen from compounds having formula (VII):

wherein:

-   -   R represents, independently of one another, a hydrogen atom; a        halogen atom, preferably chlorine; an alkyl group optionally        substituted with one or more aryl or cycloalkyl groups, with one        or more halogen atoms and/or with one or more ketone functions;        a cycloalkyl group optionally substituted with one or more alkyl        groups and/or with one or more halogen atoms; or an aryl group        optionally substituted with one or more alkyl groups and/or with        one or more halogen atoms;    -   R′ represents, independently of one another, an alkyl group        optionally substituted with one or more aryl or cycloalkyl        groups, with one or more halogen atoms and/or with a ketone        function; a cycloalkyl group optionally substituted with one or        more alkyl groups and/or with one or more halogen atoms; or an        aryl group optionally substituted with one or more alkyl groups        and/or with one or more halogen atoms;    -   R″ represents, independently of one another, a hydrogen atom; a        halogen atom, preferably chlorine; an alkyl group optionally        substituted with one or more aryl or cycloalkyl groups and/or        with one or more halogen atoms; a cycloalkyl group optionally        substituted with one or more alkyl groups and/or with one or        more halogen atoms; or an aryl group optionally substituted with        one or more alkyl groups and/or with one or more halogen atoms;        and    -   m, n and o are integers equalling 0, 1, 2 or 3, and m+n+o=3,    -   R, R′ and R″ being identical or different,        and mixtures thereof.

The hydrogenosilane compound can be chosen from compounds having formula(VII) wherein the symbols m=0, n=0 and o=3, and R″ represent a hydrogenatom, a halogen atom, preferably chlorine, a C1 to C8 linear or branchedalkyl group or an aryl group.

Among the hydrogenosilanes, mention can be made oftris(trimethylsilyl)silane, phenylsilane and triethoxysilane.

Alternatively, the hydrogenosilane compound can be chosen from compoundshaving formula (VII) wherein the symbols m=3, n=0 and o=0, and Rrepresent a hydrogen atom, a halogen atom, preferably chlorine, a C1 toC8 linear or branched alkyl group or an aryl group.

Compound B can also be an organopolysiloxane compound comprising atleast one hydrogen atom bonded to a silicon atom. The organopolysiloxanecompound comprises at least two silicon atoms, preferably at least 3silicon atoms or more.

Said compound B can advantageously be an organopolysiloxane comprisingat least one unit having formula (VIII):

H_(d)U_(e)SiO_((4−(d+e))/2)   (VIII)

wherein:

-   -   the U radicals, identical or different, represent a hydrocarbon        radical having from 1 to 12 carbon atoms,    -   d=1 or 2, e=0, 1 or 2 and d+e=1, 2 or 3;        and optionally other units having formula (IX):

U_(f)SiO_((4−f)/2)   (IX)

wherein U has the same meaning as hereinabove, and f=0, 1, 2, or 3.

It is understood in the formula (VIII) and in the formula (IX)hereinabove that, if several U groups are present, they can be identicalor different from one another. In the formula (VIII), the symbol d canpreferably be equal to 1. In addition, in the formula (VIII) and in theformula (IX), U can represent a monovalent radical chosen from the groupconsisting of an alkyl group having 1 to 8 carbon atoms, optionallysubstituted with at least one halogen atom such as chlorine or fluorine,the alkyl groups having from 1 to 8 carbon atoms, the cycloalkyl groupshaving from 3 to 8 carbon atoms and the aryl groups having from 6 to 12carbon atoms. U can advantageously be chosen from the group consistingof methyl, ethyl, propyl, 3,3,3-trifluoropropyl, xylyl, tolyl andphenyl.

These organopolysiloxanes can have a linear, branched or cyclicstructure. The degree of polymerisation is preferably greater than orequal to 2. More generally, it is less than 5,000.

When this entails linear polymers, the latter are substantiallyconstituted:

-   -   of “D” siloxyl units chosen from units having the following        formulas U₂SiO_(2/2) or UHSiO_(2/2), and    -   of “M” siloxyl units chosen from units having the following        formulas U₃SiO_(1/2) or U₂HSiO_(1/2).

These linear organopolysiloxanes can be oils with a dynamic viscosity ofabout from 1 to 100,000 mPa.s at 25° C. and more generally of about from10 to 5,000 mPa.s at 25° C.

Examples of organopolysiloxanes that can be compounds B according to theinvention comprising at least one hydrogen atom bonded to a silicon atomare:

-   -   a poly(dimethylsiloxane) with hydrogenodimethylsilyl ends;    -   a poly(dimethylsiloxane-co-methylhydrogenosiloxane) with        trimethyl-silyl ends;    -   a poly(dimethylsiloxane-co-methylhydrogenosiloxane) with        hydro-genodimethylsilyl ends;    -   a poly(methylhydrogenosiloxane) with trimethylsilyl ends; and    -   a cyclic poly(methylhydrogenosiloxane).

When this entails cyclic organopolysiloxanes, the latter are consistedof “D” siloxyl units of the following formulas U₂SiO_(2/2) andUHSiO_(2/2), which can be of the dialkylsiloxy or alkylarylsiloxy typeor of UHSiO_(2/2) units only. They then have a viscosity of about from 1to 5,000 mPa.s.

Preferably, compound B is an organopolysiloxane compound comprising permolecule at least two and preferably three hydrogenosilyl functions(Si—H).

The following compounds are particularly suitable for the invention interms of organohydrogenopolysiloxane compound B:

with a, b, c, d and e defined hereinbelow:

-   -   in the polymer having formula S1:    -   0≤a≤150, preferably 0≤a≤100, and more particularly 0≤a≤20, and    -   1≤b≤90 preferably 10≤b≤80 and more particularly 30≤b≤70,    -   in the polymer having formula S2: 0≤c≤15    -   in the polymer having formula S3: 5≤d≤200, preferably 20≤d≤100,        and 2≤e≤90, preferably 10≤e≤70.

In particular, an organohydrogenopolysiloxane compound B that issuitable for the invention is the compound having formula S1, where a=0.

Preferably the organohydrogenopolysiloxane compound B has a mass contentin motif SiH comprised between 0.2 and 91%, preferably between 0.2 and50%.

Finally, compound B can be an organic polymer comprising hydrogenosilylfunctions in terminal positions. The organic polymer can for example bea polyoxoalkylene, a saturated hydrocarbon polymer or apoly(meth)acrylate. Organic polymers comprising reactive functions interminal positions re in particular described in U.S. Patentapplications 2009/0182099 and U.S. 2009/0182091.

According to a particular embodiment of the present invention, it ispossible that the unsaturated compound A and compound B comprising atleast one hydrogenosilyl function be a single and same compound,comprising on the one hand at least one alkene function and/or an alkynefunction, and on the other hand at least one hydrogen atom bonded to asilicon atom. This compound can then be qualified as “bifunctional”, andit is susceptible to react on itself by hydrosilylation reaction. Theinvention can therefore also relate to a method of hydrosilylation of abifunctional compound with itself, said bifunctional compound comprisingon the one hand at least one alkene function and/or an alkyne function,and on the other hand at least one silicon atom and at least onehydrogen atom bonded to the silicon atom, said method beingcharacterised by the fact that it is catalysed by nanoparticles and/or acolloidal suspension comprising nanoparticles such as describedhereinabove.

Examples of organopolysiloxanes that can be bifunctional compounds are:

-   -   a        poly(dimethylsiloxane-co-hydrogenomethylsiloxane-co-vinylmethyl-siloxanes)        with dimethylvinylsilyl ends;    -   a        poly(dimethylsiloxane-co-hydrogenomethylsiloxane-co-vinylmethyl-siloxanes)        with dimethylhydrogenosilyl ends; and

When this entails the implementation of the unsaturated compound A andthe compound B comprising at least one hydrogenosilyl function, thoseskilled in the art understand that the implementation of a bifunctionalcompound is also meant.

The method of hydrosilylation according to the present invention can beimplemented at a temperature comprised between 10 and 150° C. Accordingto an embodiment, the method of hydrosilylation is implemented at atemperature comprised between 80 to 140° C. According to anotherembodiment, the method of hydrosilylation is implemented at atemperature comprised between 15 and 60° C. According to an embodiment,the method of hydrosilylation is implemented at room temperature.

“Room temperature” means in the present invention a temperaturecomprised between 15 and 25° C.

The method of hydrosilylation according to the invention can beimplemented under inert atmosphere, for example under dinitrogen.

The method of hydrosilylation according to the invention can beimplemented under UV radiation.

The method according to the invention can be implemented in the presenceor in the absence of solvent. According to a preferred embodiment, themethod according to the invention is implemented in the absence ofsolvent. According to an alternative of the invention, one of thereagents, for example the unsaturated compound A, can play the role of asolvent.

In the method according to the invention, the relative quantity ofcompound A and of compound B can be controlled in such a way as toensure the reaction rate of the unsaturations with desiredhydrogenosilyl functions. The molar ratio R of the hydrogenosilylfunctions of the compounds B over the alkene and alkyne functions of thecompounds A is comprised between 0.1:5 and 5:0.1, preferably between0.5:3 and 3:0.5, and more preferably between 1:2 and 2:1.

According to an embodiment of the method according to the invention, themolar ratio R of the hydrogenosilyl functions of the compounds B overthe alkene and alkyne functions of the compounds A is strictly greaterthan 1. The hydrogenosilyl functions are then in excess in relation tothe unsaturated functions. In this case, the method of hydrosilylationis then qualified as partial. This can also be referred to as partialfunctionalisation. The partial functionalisation can be used for exampleto obtain silicone oils with hydrogenosilyl functions and epoxyfunctions.

According to another embodiment, the molar ratio of the hydrogenosilylfunctions of the compounds B over the alkene and alkyne functions of thecompounds A is less than or equal to I. The hydrogenosilyl functions arethen lacking in relation to the unsaturated functions. This is the casewhen the unsaturated compound A plays the role of a solvent.

Advantageously, in the method according to the invention, the molarconcentration in metal coming from the nanoparticles is from 0.001% to10%, preferably from 0.01% to 5%, and more preferably from 0.05% to 3%in relation to the total number of moles of unsaturations carried by theunsaturated compound A.

According to an alternative, the nanoparticles of transition metals withan oxidation state of 0 include at least one metal chosen from Fe, Coand Ni, and, in the method according to the invention, compounds with aplatinum, palladium, ruthenium or rhodium base are not implemented.

According to a preferred embodiment of the invention, the compounds Aand B implemented are chosen from organopolysiloxanes such as definedhereinabove. In this case, a network in three dimensions is formed,which leads to the hardening of the composition. The crosslinkingimplies a progressive physical change in the medium that forms thecomposition. Consequently, the method according to the invention can beused to obtain elastomers, gels, foams etc. A crosslinked siliconematerial Y is obtained in this case. “Crosslinked silicone material”means any product with a silicone base obtained by crosslinking and/orhardening of compositions comprising organopolysiloxanes that have atleast two unsaturated bonds and organopolysiloxanes that have at leastthree hydrogenosilyl units. The crosslinked silicone material Y can forexample be an elastomer, a gel or a foam.

Still according to this preferred embodiment of the method according tothe invention, where the compounds A and B are chosen fromorganopolysiloxanes such as defined hereinabove, The usual functionaladditives can be implemented in the silicone compositions. As familiesof usual functional additives, mention can be made of:

-   -   fillers;    -   adhesion promoters;    -   inhibitors or retardants of the hydrosilylation reaction;    -   adherence modulators;    -   silicone resins;    -   additives for increasing the consistency;    -   pigments; and    -   additives for thermal resistance, resistance to oils or        resistance to fire, for example metal oxides.

The fillers optionally provided are more preferably mineral fillers.They can in particular be siliceous. When entailing siliceous materials,they can play the role of a reinforcing or semi-reinforcing filler. Thereinforcing siliceous fillers are chosen from colloidal silicas,combustion and precipitation silica powders or the mixtures thereof.These powders have an average particle size generally less than 0.1 μm(micrometres) and a BET specific surface greater than 30 m²/g,preferably comprised between 30 and 350 m²/g. Semi-reinforcing siliceouscharges such as diatomaceous earths or crushed quartz, can also be used.With regards to the non-siliceous mineral materials, they can interveneas a semi-reinforcing or stuffing mineral filler. Examples of thesenon-siliceous fillers that can be used alone or in a mixture are carbonblack, titanium dioxide, aluminium oxide, hydrated alumina, expandedvermiculite, non-expanded vermiculite, calcium carbonate optionallysurface treated with fatty acids, zinc oxide, mica, talc, iron oxide,barium sulphate and slaked lime. These fillers have a granulometrygenerally comprised between 0.001 and 300 μm (micrometres) and a BETsurface less than 100 m²/g. In a practical but non-limiting manner, thefillers used can be a mixture of quartz and of silica. The charges canbe treated by any suitable product. From a weight standpoint, it ispreferred to implement a quantity of filler comprised between 1% and 50%by weight, preferably between 1% and 40% by weight in relation to allthe constituents of the composition.

Adhesion promoters are widely used in silicone compositions.Advantageously, in the method according to the invention one or moreadhesion promoters can be implemented chosen from the group consistingof:

-   -   alkoxyl organosilanes containing, per molecule, at least one        C₂-C₆ alkenyl group, selected from the products having the        following general formula (D1):

formula wherein:

-   -   R¹, R², R³ are hydrogen or hydrocarbon radicals identical or        different between them and represent a hydrogen atom, a C₁-C₄        linear or branched alkyl or a phenyl optionally substituted with        at least one C₁-C₃ alkyl,    -   U is a C₁-C₄ linear or branched alkylene,    -   W is a valency bond,    -   R⁴ and R⁵ are identical or different radicals and represent a        C₁-C₄ linear or branched alkyl,    -   x′=0 or 1, and    -   x=0 to 2.    -   organosilicon compounds comprising at least one radical epoxy,        chosen from:        -   a) the products (D.2a) that have the following general            formula:

formula wherein:

-   -   R⁶ is a C₄-C₄ linear or branched alkyl radical,    -   R⁷ is a C₁-C₄ linear or branched alkyl radical,    -   y is equal to 0, 1, 2 or 3, and    -   X being defined by the following formula:

with:

-   -   E and D which are identical or different radicals chosen from        C₁-C₄ linear or branched alkyls,    -   z which is equal to 0 or 1,    -   R⁸, R⁹, R¹⁰ which are identical or different radicals        representing a hydrogen atom or a C₁-C₄ linear or branched        alkyl, and    -   R⁸ and R⁹ or R¹⁰ able to alternatively form together and with        the two carbons carrying the epoxy, an alkyl cycle having from 5        to 7 links, or        -   b) the products (D.2b) formed by epoxyfunctional            polydiorganosiloxanes including:            -   (i) at least one siloxyl unit having formula (D.2 bi):

$\begin{matrix}{X_{p}G_{q}{SiO}\frac{4 - \left( {p + q} \right)}{2}} & \left( {D{.2}\mspace{14mu} {bi}} \right)\end{matrix}$

formula wherein:

-   -   X is the radical such as defined hereinabove for the formula        (D.2 a)    -   G is a monovalent hydrocarbon group chosen from the alkyl groups        having from 1 to 8 carbon atoms inclusive, optionally        substituted with at least one halogen atom, and thus from the        aryl groups that contain between 6 and 12 carbon atoms,    -   p=1 or 2,    -   q=0, 1 or 2,    -   p+q=1, 2 or 3 and    -   and (ii) optionally at least one siloxyl unit having formula        (D.2 bii):

$\begin{matrix}{G_{r}{SiO}\frac{4 - r}{2}} & \left( {D{.2}\mspace{14mu} {bii}} \right)\end{matrix}$

formula wherein:

-   -   G has the same meaning as hereinabove and    -   r is equal to 0, 1, 2 or 3.    -   organosilicon compounds comprising at least one hydrogenosilyl        function and at least one radical epoxy and    -   metal chelates M and/or metal alkoxides having general formula:

M(OJ)_(n),

wherein

-   -   M is chosen from the group formed by: Ti, Zr, Ge, Li, Mn, Fe, Al        and Mg or the mixtures thereof    -   n=valence of M and J=C₁-C₈ linear or branched alkyl.

Preferably M is chosen from the following list: Ti, Zr, Ge, Li or Mn,and more preferably the metal M is Titanium. It is possible to associatewith it, for example, a radical alkoxy of the butoxy type.

Silicone resins are well-known branched organopolysiloxane oligomers orpolymers available off-the-shelf. They have, in their structure, atleast two different units chosen from those having formula R₃SiO_(1/2)(M unit), R₂SiO_(2/2) (D unit), RSiO_(3/2) (T unit) and SiO_(4/2) (Qunit), at least one of these units being a T or Q unit.

The R radicals are identical or different and are chosen from C1-C6linear or branched alkyl radicals, hydroxyl, phenyl, trifluoro-3,3,3propyl. Mention can be made of for example as alkyl radicals, methyl,ethyl, isopropyl, tertiobutyl and n-hexyl radicals.

As examples of branched organopolysiloxane oligomers or polymers,mention can be made of MQ resins, MDQ resins, TD resins and MDT resins,the hydroxyl functions that can be carried by the M, D and/or T units.As an example of resins that are particularly suitable, mention can bemade of hydroxylated MDQ resins that have a weight content in hydroxylgroup comprised between 0.2 and 10% by weight.

Composition

The present invention also has for object, a composition X comprising:

-   -   at least one unsaturated compound A such as defined hereinabove,    -   at least one compound B comprising at least one hydrogenosilyl        function such as defined hereinabove, and    -   nanoparticles or a colloidal suspension comprising nanoparticles        such as defined hereinabove.

According to another embodiment of the invention, the composition X is acrosslinkable composition comprising:

-   -   at least one unsaturated compound A including, per molecule, at        least two C₂-C₆ alkenyl radicals bonded to silicon atoms and,        preferably, chosen from the organopolysiloxane compounds        including units having formula (V):

Z_(g)U_(h)SiO_((4−(g+h))/2)   (V)

wherein:

-   -   the Z radicals, identical or different, represent an alkenyl        radical, linear or branched, having from 2 to 6 carbon atoms;    -   the U radicals, identical or different, represent a hydrocarbon        radical having from 1 to 12 carbon atoms,    -   g=1 or 2, h=0, 1 or 2 and g+h=1, 2 or 3;    -   and including optionally other units having formula (VI):

USiO_((r−i)/2)   (VI)

wherein U has the same meaning as hereinabove, and i =0.1, 2, or 3,

-   -   at least one organohydrogenopolysiloxane compound B including,        per molecule, at least two hydrogen atoms, preferably at least        three, bonded to an identical or different silicon atom, and    -   nanoparticles or a colloidal suspension comprising nanoparticles        such as defined hereinabove.

According to a preferred embodiment of the invention, the composition Xaccording to the invention is a crosslinkable composition, whereincompound B is chosen from the organopolysiloxanes comprising at leastone unit having formula (VIII):

H_(d)U_(e)SiO_((4−(d+e))/2)   (VIII)

wherein:

-   -   the U radicals, identical or different, represent a hydrocarbon        radical having from 1 to 12 carbon atoms,    -   d=1 or 2, e=0, 1 or 2 and d+e=1, 2 or 3;        and optionally other units having formula (IX):

U_(f)SiO_((4−f)/2)   (IX)

wherein U has the same meaning as hereinabove, and f=0.1, 2, or 3.

The molar concentration in metal, coming from nanoparticles, of thecomposition X according to the invention is comprised between 0.01% and15%, preferably between 0.05% and 10%, and more preferably between 0.1%and 4% in relation to the total number of moles of unsaturations carriedby the unsaturated compound A.

According to an embodiment, the composition X according to the inventionis free of catalyst with a platinum, palladium, ruthenium or rhodiumbase. “Free” from catalyst means that the composition X according to theinvention comprises less than 10′ % by weight of catalyst with aplatinum, palladium, ruthenium or rhodium base, preferably less than10⁻²% by weight, and more preferably less than 1% by weight, in relationto the total weight of the composition.

According to a particular embodiment, the composition X according to theinvention also comprises one or more usual functional additives insilicone compositions. As families of usual functional additives,mention can be made of:

-   -   fillers;    -   adhesion promoters;    -   inhibitors or retardants of the hydrosilylation reaction;    -   adherence modulators;    -   silicone resins;    -   additives for increasing the consistency;    -   pigments; and    -   additives for thermal resistance, resistance to oils or        resistance to fire, for example metal oxides.

The compositions X according to the invention can in particular beobtained by introducing under inert atmosphere firstly the nanoparticlesor the colloidal suspension comprising nanoparticles in the reactionmedium, then by adding compound A under stirring. Finally, compound B isintroduced and, if necessary, the temperature of the mixture isincreased in order to reach the reaction temperature.

The invention also has for object a crosslinked silicone material Yobtained by heating to a temperature ranging from 15° C. and 150° C., ofa crosslinkable composition X comprising:

-   -   at least one unsaturated compound A including, per molecule, at        least two C₂-C₆ alkenyl radicals bonded to silicon atoms and        chosen from the organopolysiloxane compounds including units        having formula (V):

Z_(g)U_(h)SiO_((4−(g+h))/2)   (V)

wherein:

-   -   the Z radicals, identical or different, represent an alkenyl or        alkynyl radical, linear or branched, having from 2 to 6 carbon        atoms;    -   the U radicals, identical or different, represent a hydrocarbon        radical having from 1 to 12 carbon atoms,    -   g=1 or 2, h=0, 1 or 2 and g+h=1, 2 or 3;

and including optionally other units having formula (VI):

U_(i)SiO_((4−i)/2)   (VI)

wherein U has the same meaning as hereinabove, and i =0, 1, 2, or 3,

-   -   at least one organohydrogenopolysiloxane compound B including,        per molecule, at least two hydrogen atoms bonded to an identical        or different silicon atom, and    -   nanoparticles or a colloidal suspension comprising nanoparticles        such as defined hereinabove.

The present invention is shown in more detail in the non-limitingembodiments.

EXAMPLES Example 1 Synthesis of Fe Nanoparticles with an Oxidation stateof 0

Under inert atmosphere, 276.9 mg (0.55 mmol) of Fe₃(CO)₁₂ and 50 mL ofdry and degassed toluene are added to a Fisher-Porter reactor equippedwith a magnetic stirrer bar. While maintaining stirring, 96 μL (0.5mmol) of n-octylsilane are added to the solution. The whole ispressurised under 3 bars of hydrogen and heated to 80° C. for 24 h.After cooling, the solution is transferred into a Schlenk and kept underargon.

The average diameter of the iron nanoparticles was measured by HAADFSTEM (Scanning Transmission Electron Microscopy in the High AngleAnnular Dark Field imaging mode). FIG. 1A shows a HAADF STEM photo ofthe colloidal solution comprising iron nanoparticles. FIG. 1B shows thenumber of nanoparticles according to their diameter. The averagediameter of the nanoparticles is 2.6 nm±0.7 nm. The iron nanoparticlesimpregnated on SiO₂ were analysed by infrared spectroscopy and comparedto the precursor used (Fe₃(CO)₁₂). FIG. 2 shows the results obtained.These results show that there is no longer any precursor present in thenanoparticles and that the carbonyl ligands are well coordinated to theiron of the nanoparticles. Moreover, the peaks between 2,800 and 3,000cm⁻¹ demonstrate the presence of at least one silicide on thenanoparticles.

The nanoparticles were also characterised by NMR. FIG. 3 shows the¹³C-NMR spectrum of the iron nanoparticles and of the precursor used(Fe₃(CO)₁₂) between 180 and 230 ppm. These results show that theprecursor is transformed and that the carbonyl ligands are wellcoordinated to the iron of the nanoparticles. FIG. 4 shows the ¹H-NMRspectrum of the iron nanoparticles and of the n-octylsilane. Theseresults show that the n-octylsilane did indeed react with Fe₃(CO)₁₂because the peak at 3.6 ppm is no longer visible.

The nanoparticles were also characterised by Mossbauer spectroscopy.FIG. 9 shows the Mossbauer spectrum obtained. This spectrum shows thatthe nanoparticles obtained include iron with an oxidation state of 0, atleast one silicide and that they do not have any magnetic contribution,therefore they are not paramagnetic.

The operating procedure hereinabove was also used to synthesisenanoparticles by varying the temperature and the iron precursor (cf.table 1).

Comparative Example 1 Synthesis of Fe Nanoparticles Without CO Ligand

Iron nanoparticles that do not contain any carbonyl ligand were alsosynthesised. These nanoparticles were synthesised according to theoperating procedure hereinabove at 120° C., using Fe(C₈H₈)₂ and under 3bars CO. Despite the CO atmosphere, the nanoparticles obtained do notinclude carbonyl ligand.

Comparative Example 2 Synthesis of Fe Nanoparticles at 140° C.

Iron nanoparticles were also synthesised according to the operatingprocedure of example 1 at 140° C. The iron nanoparticles impregnated onSiO₂ were analysed by infrared spectroscopy. The spectrum obtained showsthat the iron nanoparticles prepared at 140° C. do not include carbonylligand.

Example 2 Synthesis of Co Nanoparticles with an Oxidation State of 0

Under inert atmosphere, 188 mg (0.55 mmol) of Co₂(CO)₈ and 50 mL of dryand degassed toluene are added to a Fisher-Porter reactor provided witha magnetic stirrer bar. While maintaining stirring, 64 μL (0.33 mmol) ofn-octylsilane are added to the solution. The whole is pressurised under3 bars of hydrogen and heated to 80° C. for 24 h. After cooling, thesolution is transferred into a Schlenk and kept under argon.

The average diameter of the cobalt nanoparticles was measured by HAADFSTEM. FIG. 5A shows a HAADF STEM photo of the colloidal solutioncomprising cobalt nanoparticles. FIG. 5B shows the number ofnanoparticles according to their diameter. The average diameter of thenanoparticles is 1.6 nm±0.3 nm.

The infrared spectrum of the cobalt nanoparticles impregnated on SiO₂was conducted and compared to that of the precursor used (Co₂(CO)₈) FIG.6 shows the results obtained. These results show that there is no longerany precursor and that carbonyl ligands coordinated to the cobalt of thenanoparticles are indeed obtained.

The nanoparticles were also characterised by NMR. FIG. 7 shows the¹³C-NMR spectrum of the cobalt nanoparticles and of the precursor used(Co₂(CO)₈) between 180 and 230 ppm. These results show that there is nolonger any precursor and that the carbonyl ligands are well coordinatedto the cobalt of the nanoparticles. FIG. 4 shows the ¹H-NMR spectrum ofthe cobalt nanoparticles and of the n-octylsilane. These results showthat the n-octylsilane did indeed react with Co₂(CO)₈ because the peakat 3.6 ppm is no longer visible.

The operating procedure hereinabove was also used to synthesisenanoparticles by varying the temperature and the atmosphere (cf. table2).

Example 3 Hydrosilylation Reaction with Synthesised Nanoparticles

Under inert atmosphere, 0.68 mL (2.5 mmol) of MD′M (with M:(CH₃)₃Si_(1/2,) and D′: (CH₃)HSiO_(2/2)), 0.77 mL (2.5 mmol) of 1-octeneand 0.25 mL (1.1 mmol) of dodecane are added to a Schlenk provided witha magnetic stirrer bar. In this mixture, 1.5 mL of colloidal suspensionin the toluene containing 0.05 mmol of Fe (tests 1-4, table 1) or 0.033mmol of Co (tests 5-8, table 2) is added. The reaction mixture obtainedis stirred for 24 h at 120° C. in the case of the catalyst with Fe or atroom temperature if the catalyst with Co is used. The change in thereaction is controlled via GC (gas chromatography). The results areshown in tables 1 and 2.

TABLE 1 Reaction with, as a catalyst, the iron nanoparticles with anoxidation state of 0 Catalyst Conv. Yield Synthesis % mol of Fe TimeRatio Temp. MD'M produced HS Test conditions (alkene base) (h)SiH/alkene (° C.) (%) (%) 1 0.3 equiv. of 2 24 1 120 26  16 n-octylsilane, Fe₃(CO)₁₂, 80° C., 3 bars H₂ 2 0.3 equiv. of 2 24 1 12044  20  n-octylsilane, Fe₃(CO)₁₂, 120° C., 3 bars H₂ 3 0.3 equiv. of 224 1 120 30  20  n-octylsilane, Fe(CO)₅, 120° C., 3 bars H₂ 4 0.3 equiv.of 2 24 1 120 0 0 n-octylsilane, Fe(C₈H₈)₂, 120° C., 3 bars CO(comparative example 1)  4′ 0.3 equiv. of 2 24 1 120 <1% <1%n-octylsilane, Fe₃(CO)₁₂, 140° C., 3 bars H₂ (comparative example 2)

These results show that the iron nanoparticles synthesised according toexample 1 catalyse the hydrosilylation reaction between the MD′M and the1-octene (tests 1 to 3). The dehydrogenative silylation product is alsoobserved as well as isomerisation products of 1-octene.

These results also show that the iron nanoparticles that do not compriseCO ligand do not catalyse the hydrosilylation reaction (tests 4 and 4′).The presence of at least one ligand CO on the nanoparticles isessential.

TABLE 2 Reaction with, as a catalyst, the cobalt nanoparticles with anoxidation state of 0 Conv. Yield % mol of Co Time Ratio Temp. MD'Mproduced HS Test Catalyst (alkene base) (h) SiH/alkene (° C.) (%) (%) 50.075 equiv. 1.3 24 1 RT 88 73 of n-octylsilane, Co₂(CO)₈, 80° C., 3bars H₂ 6 0.075 equiv. 0.13 17 1 RT 78 71 of n-octylsilane, Co₂(CO)₈,80° C., 3 bars H₂ 7 0.075 equiv. 1.3 24 1 RT 90 77 of n-octylsilane,Co₂(CO)₈, 60° C., 3 bars H₂ 8 0.075 equiv. 1.3 24 1 RT 94 81 ofn-octylsilane, Co₂(CO)₈, room temperature, N₂

These results show that the cobalt nanoparticles synthesised accordingto example 2 catalyse the hydrosilylation reaction between the MD′M andthe 1-octene. The dehydrogenative silylation product is also observed aswell as isomerisation products of 1-octene.

These results also show that the nanoparticles can be synthesised underinert atmosphere or under pressure of hydrogen (test 8).

Example 4 Hydrosilylation Reaction on More Substantial Quantities andwith Another Alkene

In a three-neck flask provided with a refrigerant, under a nitrogenflush are introduced 2 g of MD′M, alkene, dodecane (GC internalstandard) and where applicable toluene (solvent). The colloidalsuspension of cobalt nanoparticles (with a metal precursor concentration22 μmol/mL, synthesised according to example 2 with the conditions oftest 8, table 2) is then added under stirring at room temperature. Thereaction crude is then analysed by ¹H-NMR and by GC. The results areshown in table 3.

TABLE 3 Hydrosilylation reaction with 2 g of MD'M and ether glycidylallyl % mol of Co Yield Colloidal (alkene Ratio Conv. produced TestAlkene Solvent suspension base) Alkene/SiH MD'M (%) HS (%) 9 1-octene1-octene 4.6 mL 0.05% 21.2 72% after Unde- (21.3 g) 20 h termined 10Ether Toluene 4.5 mL 0.85% 1.3 11% after Unde- glycidyl (20.2 g) 1 h40termined allyl

For tests 9 and 10, the analyses ¹H-NMR show that the hydrosilylationproduct is obtained. These results show that the cobalt nanoparticlessynthesised according to example 2 catalyse the hydrosilylation reactionbetween the MD′M and the ether glycidyl allyl. These results also showthat the unsaturated compound can play the role of a solvent.

1. Nanoparticles comprising: at least one transition metal with anoxidation state of 0, chosen from the metals of columns 8, 9 and 10 ofthe periodic table, and at least one carbonyl ligand.
 2. Nanoparticlesaccording to claim 1, wherein the metal is chosen from the groupconsisting of Fe, Co and Ni.
 3. Nanoparticles according to claim 1further comprising a silicide, preferably silicide chosen from compoundshaving formula (I):Y_(p)Z⁴ _(q)SiH_(r)   (I) wherein: the symbol(s) Y, identical ordifferent, represent a metal chosen from the metals of columns 8, 9 and10 of the periodic table, preferably a metal chosen from Fe, Co and Ni;the symbol(s) Z⁴, identical or different, represent a monovalenthydrocarbon group having from 1 to 18 carbon atoms inclusive optionallysubstituted with heteroatoms or with radicals comprising heteroatoms,and preferably chosen from the group consisting of alkyl groups havingfrom 1 to 18 carbon atoms inclusive and aryl groups having from 6 to 12carbon atoms, and more preferably chosen from the group consisting ofalkyl groups having 4 to 12 carbon atoms inclusive; p=1, 2 or 3; q=1, 2or 3, preferably q=1; r=0, 1 or 2; p+q+r=4.
 4. Nanoparticles accordingto claim 1, wherein said nanoparticles have an average diameter lessthan or equal to 10 nm.
 5. Colloidal suspension containing nanoparticlesaccording to claim
 1. 6. Catalyst comprising nanoparticles according toclaim
 1. 7. Catalyst according to claim 6, wherein said catalyst is ahydrosilylation and/or dehydrogenative silylation catalyst.
 8. Methodfor preparing nanoparticles according to claim 1, said method comprisinga step of mixing at least one metal complex, chosen from the transitionmetal carbonyls of columns 8, 9 and 10 of the periodic table, with atleast one silane in a solvent, under inert atmosphere and/or underhydrogen.
 9. Method according to claim 8 wherein the silane is acompound having formula (II):Z⁴ _(q)SiH_((4−q))   (II) wherein the symbol(s) Z⁴, identical ordifferent, represent a monovalent hydrocarbon group having from 1 to 18carbon atoms inclusive optionally substituted with heteroatoms or withradicals comprising heteroatoms, and preferably chosen from the groupconsisting of alkyl groups having from 1 to 18 carbon atoms inclusiveand aryl groups having from 6 to 12 carbon atoms, and more preferablychosen from the group consisting of alkyl groups having 4 to 12 carbonatoms inclusive; q−1, 2 or 3, preferably q−1.
 10. Method according toclaim 8, wherein the mixing step is carried out at a temperaturecomprised between 10 and 135° C., preferably 10 and 120° C.
 11. Methodfor preparing hydrosilylation and/or dehydrogenative silylation productsby reaction between: an unsaturated compound A, and a compound Bcomprising at least one hydrogenosilyl function, wherein said method iscatalysed by nanoparticles according to claim
 1. 12. Composition Xcomprising: at least one unsaturated compound A, at least one compound Bcomprising at least one hydrogenosilyl function, and nanoparticlesaccording to claim
 1. 13. Method according to claim 11, wherein saidmethod is implemented under UV radiation.
 14. Catalyst comprising acolloidal suspension according to claim
 5. 15. Method for preparing thecolloidal suspension according to claim 5, said method comprising a stepof mixing at least one metal complex, chosen from the transition metalcarbonyls of columns 8, 9 and 10 of the periodic table, with at leastone silane in a solvent, under inert atmosphere and/or under hydrogen.16. Method for preparing hydrosilylation and/or dehydrogenativesilylation products by reaction between: an unsaturated compound A, anda compound B comprising at least one hydrogenosilyl function, whereinsaid method is catalysed by a colloidal suspension according to claim 5.